Filament testers



E. P. CARTER ETAL 3,209,583

FILAMENT TESTERS Oct. 5, 1965 Filed Nov. 9. 1961 2 SheetsSheet l INVENTORS ERNEST I? CARTER LOUIS H. SAFLEY ZMKM ATTORNE United States Patent 3,209,583 FILAMENT TESTERS Ernest P. Carter and Louis H. Safley, Durham, N.C., as-

signors, by mesne assignments, to Monsanto Company, a corporation of Delaware 7 Filed Nov. 9, 1961, Ser. No. 151,271 Claims. (Cl. 73-91) This invention relates to filament testers and more particularly to apparatus for continuously winding and unwinding a filament on a mandrel until the filament breaks.

In the manufacture of chemical textile fibers great effort is expended to obtain certain desired physical properties. One of the physical properties that is important is the ability of a filament to withstand flexing and bending. One of the problems in the past has been the testing of this characteristic of filaments. With this in mind, one of the objects of this invention is to provide a novel and improved filament testing apparatus.

Another object of this invention is to provide an apparatus for flexing a filament to failure.

A further object of this invention is to provide an apparatus for winding and unwinding a filament on a mandrel until the filament breaks.

A still further object of this invention is to provide an apparatus having a mandrel which is rotated first in one direction and then in the other for Winding and unwinding a filament attached to the mandrel.

One embodiment of the present invention contemplates an apparatus having a reversing mechanism for rotating a small mandrel first in one direction and then the other to wind and unwind a filament attached to and wrapped around the mandrel. When the filament breaks, a Weight attached thereto opens a switch to stop the operation, while a timer indicates the duration of the test.

Other objects and advantages of the invention will become apparent when the following detailed description is read in conjunction with the drawings, in which FIGURE 1 is a perspective view of an apparatus illustrating one embodiment of the invention and showing the general arrangement of the various elements of the apparatus, and

FIGURE 2 is a schematic diagram of a circuit utilized to control the apparatus.

Referring now in detail to the drawing, a base 11 is shown supporting a pair of spaced parallel plates 12 and 13 upon which is rotatably mounted a shaft 17 which carries a chuck 18. The chuck 18 holds one end of a resilient bow 21 having a substantially arcuate configuration. The bow 21 is held in this configuration by a very thin wire 22 which is welded at its ends to the bow 21 to serve as a mandrel. The bow, being resilient, pulls the wire 22 taut.

A filament 26 to be tested is attached at one end to a hook 27 on the chuck 18 and is wrapped several turns around the wire mandrel 22 and at its. other end supports a weight 28. A reversible motor 32 drives the shaft 17 to rotate the wire mandrel 22 to thereby wind and unwind the filament 26 on the mandrel 22, depending upon the direction of rotation of the motor 32.

To provide for alternate rotation of the wire mandrel 22 in opposite directions a reversing mechanism 33 is provided. The reversing mechanism 33 includes an actuator 34, a normally closed Forward switch 37, and a Reverse switch 38 connected in the circuit illustrated in FIGURE 2. The actuator 34 is threaded onto a threaded or screw portion 39 of the shaft 17 so that rotation of this shaft moves the actuator 34 from the plate 12 toward the plate 13 or vice versa. A pin 42 mounted on the plates 12 and 13 extends through an aperture in the actuator 34 to prevent its rotation with the screw 39.

The switches 37 and 38 are provided with plungers 45 and 46 which are engaged by the moving actuator 34 to change the direction of rotation of the motor 32. It can be seen that, as the motor 32 is driven first in one direction and then the other, the wire mandrel 22 will be alternately rotated in opposite directions to wind and unwind the filament 26 until it breaks.

FIGURE 2 illustrates the circuit which controls the apparatus; To begin operation, an On-01f switch 50 is manually closed to connect a motor controller 51 of a well known type to a power supply 52. The operator then momentarily closes a Start switch 55 to energize a relay 56 through a normally closed Stop switch 57. Energization of the relay 56 closes a contact 60 to lock in the relay 56 and also closes a contactor 61 to apply power to the remainder of the circuit.

Closure of the contact 61 energizes a relay 64 which closes its contactor 65 to connect the mot-or controller 51 to the motor 32 through a pair of normally closed contacts 66 of a relay 67. This starts the motor 32 rotating in a direction to wind the filament 26 onto the mandrel 22 to move the actuator 34 toward the Reverse switch 38.

The motor 32 rotates the shaft 17 and the screw 39 to move the actuator 34 in a forward direction toward the Reverse switch 38 until the actuator 34 engages the plunger 46 and closes the switch 38 to energize the relay 67 and a locking relay 71. The locking relay 71 closes its contactor 72 to maintain the relay 67 and 71 in an energized state until the actuator 34 completes its reverse movement and opens the Forward switch 37.

Energization of the relay 67 opens the contacts 66 and closes a pair of contacts 73 to reverse the direction of rotation of the motor 32. This reverses the direction of the motor 32 to unwind the filament from the mandrel 22 and to move the actuator 34 toward the Forward switch 37. When the actuator 34 engages the plunger 45 and opens the normally closed Forward switch 37, the relays 67 and 71 drop out.

Deenergization of the relay 67 opens the contacts 73 and closes the contacts 66 to drive the motor in its forward direction. Deenergization of the relay 71 opens the contact 72 to prevent energization of the relays 67 and 71 until the actuator 34 has completed its forward movement.

Upon completion of its forward movement, the actuator 34 again engages the plunger 46 and closes the Reverse switch 38 to again change the direction of the motor 32 and, consequently, the direction of rotation of the mandrel 22. This alternating rotation of the mandrel 22 continues until the filament 26 breaks, whereupon the weight 28 drops into a pan 75 (FIG. 1) attached to the Stop switch 57. This opens the switch 57 to drop out the relay 56 to thereby open the contact 61 and disconnect the circuit from the power supply 52.

A timer 76 connected in the circuit as shown indicates the time interval from the closure of the Start switch 55 to the openings of the Stop switch 57 by the falling weight. Knowing the rate at which the mandrel 22 is turned, the amount of winding and unwinding of the filament 22 can be determined.

It is to be understood that the embodiment disclosed herein may be modified or amended and that numerous other embodiments may be contemplated which will fall within the spirit and scope of the invention.

What is claimed is:

1. An apparatus for testing a filament, comprising a base, a flexible wire mandrel, means rotatably mounted above the base and secured to the ends of the flexible wire mandrel for tensioning and rotating said flexible wire mandrel, holding means on said means rotatably mounted for holding one end of a filament, means on the base for rotating said means rotat-ably mounted first in one direction and then in the other to wind and unwind a filament wound around said mandrel, the filament having one end attached to said holding means and the other end attached to and suspending a weight, and means on the base for stopping the rotating means when the filament breaks.

2. An apparatus for testing a filament, comprising a base, a shaft mounted above the base, a resilient bow secured to the shaft and rotatable therewith, a flexible wire mandrel suspended under tension between spaced points on said bow, means on the shaft for securing one end of the filament, and means for alternately rotating the shaft in opposite direction to wind and unwind a filament which is wrapped about said flexible wire mandrel and which has one end attached to said securing means and the other end attached to and suspending a weight.

3. An apparatus for testing a filament, comprising a base, a resilient bow positioned above the base and having secured thereto at spaced points thereon a wire, said wire holding the bow in a curved configuration and said bow holding said wire taut, rotatable means supporting the bow and including means for holding one end of a filament wrapped around the wire and having a weight secured to suspended from its other end, and means on the base for rotating said rotatable support means to reversibly wind the filament around said wire.

4. An apparatus for testing filaments by subjecting the filaments to flexure and bending over a small radius of curvature, comprising a flexible wire mandrel, mandrel mounting means secured to the ends of the flexible wire mandrel and axially tensioning said mandrel, means mounted on the mandrel mounting means for securing one end of a filament to be tested, said mounting means being mounted for reversible rotation so that a filament wrapped around said mandrel and having one end attached to the securing means and the other end attached to and suspending a weight may be alternately wound and unwound about said flexible wire mandrel.

5. The invention as defined in claims 4 wherein said mandrel mounting means includes a resilient bow, said flexible wire mandrel being tensioned between spaced points on said bow.

References Cited by the Examiner UNITED STATES PATENTS 1,436,323 11/22 Schnable et al 73100 1,644,545 10/27 Robertson 318-282 2,488,761 11/49 Budd et a1. 73100 3,065,632 1l/62 Crane et a l 73l00 X RICHARD C. QUEISSER, Primary Examiner. 

1. AN APPARATUS FOR TESTING A FILAMENT, COMPRISING A BASE, A FLEXIBLE WIRE MANDREL, MEANS ROTATABLY MOUNTED ABOVE THE BASE AND SECURED TO THE ENDS OF THE FLEXIBLE WIRE MANDREL FOR TENSIONING AND ROTATING SAID FLEXIBLE WIRE MANDREL, HOLDING MEANS ON SAID MEANS ROTATABLY MOUNTED FOR HOLDING ONE END OF A FILAMENT, MEANS ON THE BASE FOR ROTATING SAID MEANS ROTATABLY MOUNTED FIRST IN ONE DIRECTION AND THEN IN THE OTHER TO WIND AND UNWIND A FILAMENT WOUND AROUND SAID MANDREL, THE FILAMENT HAVING ONE END ATTACHED TO SAID HOLDING MEANS AND THE OTHER END ATTACHED TO AND SUSPENDING A WEIGHT, AND MEANS ON THE BASE FOR STOPING THE ROTATING MEANS WHEN THE FILAMENT BREAKS. 